root: remove redundant cmake flags

This commit suggests to remove CMake flags that are the same as the
default in ROOT.

Many of these flags were useful in the past, but in the last years the
default built configuration of ROOT was improved and many toggles are
now unnecessary.

Removing the redundant flags makes it clearer what the differences of
the package to the default configuration are, and it's also more
future-proof in case flags get deprecated or removed.

pkgs/applications/science/misc/root/default.nix

···
   '';
 
   cmakeFlags = [
-    "-Drpath=ON"
     "-DCMAKE_INSTALL_BINDIR=bin"
     "-DCMAKE_INSTALL_LIBDIR=lib"
     "-DCMAKE_INSTALL_INCLUDEDIR=include"
     "-Dbuiltin_llvm=OFF"
-    "-Dbuiltin_freetype=OFF"
-    "-Dbuiltin_gtest=OFF"
-    "-Dbuiltin_nlohmannjson=OFF"
-    "-Dbuiltin_openui5=ON"
     "-Dclad=OFF"
-    "-Ddavix=ON"
-    "-Ddcache=OFF"
     "-Dfail-on-missing=ON"
-    "-Dfftw3=OFF"
     "-Dfitsio=OFF"
-    "-Dfortran=OFF"
     "-Dgnuinstall=ON"
-    "-Dimt=ON"
-    "-Dgviz=OFF"
-    "-Dhttp=ON"
     "-Dmysql=OFF"
-    "-Dodbc=OFF"
-    "-Dopengl=ON"
     "-Dpgsql=OFF"
-    "-Dpythia8=OFF"
-    "-Droot7=ON"
     "-Dsqlite=OFF"
-    "-Dssl=ON"
-    "-Dtmva=ON"
     "-Dtmva-pymva=OFF"
     "-Dvdt=OFF"
-    "-Dwebgui=ON"
-    "-Dxml=ON"
-    "-Dxrootd=ON"
   ]
   ++ lib.optional (stdenv.cc.libc != null) "-DC_INCLUDE_DIRS=${lib.getDev stdenv.cc.libc}/include"
   ++ lib.optionals stdenv.isDarwin [